A steel rail of length 5 m and area of cross section 40 cm^2is prevented from expanding along its length while the temperature rises by 10^@C . If coefficient of linear expansion and Young's modulus of steel are 1.2 xx 10^5K^1and 2 xx 10^11 Nm^2respectively, the force developed in the rail is approximately:

A steel rail of length 5 m and area of cross section 40 cm^2is prevent

1.	A steel rail of length 5 m and area of cross section 40 cm^2is prevented from expanding along its length while the temperature rises by 10^@C . If coefficient of linear expansion and Young's modulus of steel are 1.2 xx 10^5K^1and 2 xx 10^11 Nm^2respectively, the force developed in the rail is approximately:
Answer» `2 xx 10^7 N` `1 xx 10^5 N` `2 xx 10^9 N` `3 xx 10^(-5) N` Solution :`F = AY alpha Delta T = 40 xx 10^(-2) xx 2 xx 10^11 xx 1.2 xx 10^5 xx 10 = 0.96 xx 10^5 ~~ 1 xx 10^5 N`